HAL Id: hal-01608682
https://hal.archives-ouvertes.fr/hal-01608682
Submitted on 2 Jun 2020
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Distributed under a Creative Commons Attribution - ShareAlike| 4.0 International License
Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated digestion conditions
Oana-Crina Bujor, Christian Ginies, Valentin I. Popa, Claire Dufour
To cite this version:
Oana-Crina Bujor, Christian Ginies, Valentin I. Popa, Claire Dufour. Phenolic extracts of bilberry:
they protect lipid from oxidation in in vitro simulated digestion conditions. ICP 2016 - XXVIIIth
International Conference on Polyphenols, Jul 2016, Vienna, Austria. 2016. �hal-01608682�
Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated
digestion conditions
Oana-Crina Bujor (a,b) , Christian Ginies (a) , Valentin I. Popa (b) , Claire Dufour (a)
a
UMR408 SQPOV "Safety and Quality of Plant Products", INRA, Université d'Avignon, F-84000 Avignon, France
b
“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 700050 Iasi, Romania
Centre Inra Provence-Alpes-Côte d’Azur 228 route de l’aérodrome
Domaine Saint Paul, Site Agroparc CS 40 509
84914 Avignon Cedex 9 http://www.paca.inra.fr
Polyunsaturated Fatty Acids(TG, PL, chlolesterol esters) +
Dietary iron + O2, H+
Polyphenol consumption/day 0,8-1,3 g [1]
Polyphenols bioaccessibility [PP] natifs≈0,5 - 1 mM Lipid oxidation products
(LOOH, L=O, LOH…). [2]
Absorbed in LDL Atherogenicity of modified LDL
BACKGROUND
Bilberry (BB) (Vaccinium myrtillusL.) polyphenols:
content and main contributors [3]
Stems 79 mg/g DE A-type trimer B-type dimer
5-O-Caffeoylquinic-acid Fruits
27 (H2O) mg/g DE 41 (aq. EtOH) mg/g DE delphinidin-3-O-glucoside Leaves
125 mg/g DE 5-O-Caffeoylquinic-acid
MATERIALS AND METHODS
oil-in-water Emulsionstabilized by:
- BSA (Bovine Serum Albumin) - PL(egg yolk phospholipids)
Metmyoglobin [20 μM]final
pH 5 (initial stage of digestion)
37 °C, 6 h Lipid-derived conjugated dienes
(CDs) Abs. at 234 nm stems
leaves
fruits [0.1 mg DE/mL]
[0.2 mg DE/mL]
BB samples from July 2013
Leaves
Stems
Fruits
References:
[1] Pérez-Jiménez J. et al., Am. J. Clin. Nutr., 2011, 93, 1220–8.
[2] Ursini F. and Sevanian A., Biol. Chem., 2002, 383, 599–605.
[3] Bujor et al., Food Chem, submitted.
[4] Lorrain et al., J Agric Food Chem., 2012, 60, 9074−9081.
[5] Minekus M. et al., Food & Function, 2014, 5, 1113-24.M
Oral Phase Gastric Phase Intestinal Phase
Mix:
dietary lipids (BSA or PL emulsions)
+ Leaf extract (36 mg)
+ CaCl2(0.75 mM)
Adjustment pH 7:
1 M NaOH
Incubation:
5 min, 37 °C, 130 rpm
No sampling
Oral phase (1:1 dilution with SGF)
+ pepsin (2000 U/mL)
+ MbFeIII(20 μM)
Adjustment pH 5:
1 M HCl
Incubation: Sampling:
1 h, 37 °C, 280 rpm; 0, 30, 60 min
Adjustment pH 3:
1 M HCl
Incubation: Sampling:
1 h, 37 °C, 280 rpm; 90, 120 min
Gastric phase (1:1 dilution with SIF)
+ pancreatin (100 U/mL)
+ bile (10 mM)
+ CaCl2(0.49 mM)
Adjustment pH 6.5:
1 M NaOH
Incubation:
2 h, 37 °C, 280 rpm
Sampling:
0, 30, 60, 90, 120 min
Determination of CDs Determination of CDs
In vitro model of oro-gastrointestinal digestion [5]
In vitro model of gastric digestion [4]
RESULTATS AND DISCUSSIONS
CONCLUSIONS
Leaf, stem and fruit extracts of bilberry can play a protective role towards oxidation of polyunsaturated dietary lipids during digestion.
The fast lipid oxidation in the gastric step (BSA and PL emulsion systems) and the slower lipid oxidation in the intestinal step (PL system) were totally inhibited by a bilberry leaf extract at the level of 3 mg/mL in the gastric step.
the stability of the phenolic compounds should be further evaluated in the gastrointestinal digestion to give an insight into their protective mechanisms.
Gastric digestion: Inhibition of lipid oxidation
Oro-gastrointestinal digestion: Inhibition of lipid oxidation
0 50 100 150 200 250 300
0 30 60 90 120
μmol CD / g lipids
Digestion time (min) Gastric step
0 100 200 300 400 500 600
0 30 60 90 120
μmol CD / g lipids
Digestion time (min)
Control Leaf extract Intestinal step
In BSA-stabilized emulsions
0 50 100 150
0 30 60 90 120
μmol CD / g lipids
Digestion time (min) Gastric step
0 100 200 300 400 500
0 30 60 90 120
μmol CD /g lipids
Digestion time (min)
Control Leaf extract Intestinal step
In PL-stabilized emulsions
Gastric step: lipid oxidation was 2-fold slower than in the BSA model. Totally inhibited by the stem extract.
Intestinal step: weak lipid oxidation. Antioxidant action of the leaf extract preserved.
Gastric step: fast lipid oxidation between t0 and 120 minmetmyoglobin was likely the prooxidant form for the 1st hour when hematin may be released from MbFeIII during the 2ndhour. The leaf extract at a dietary concentration (3 mg/mL) totally inhibited lipid oxidation.
Intestinal step: weak increase in CD levels from 162 to 226 μmol/g lipids over the two hours of study. Inhibition by the stem extract is kept.
1. Microwave-assisted extraction (1% citric acid in water
or 55% aq. EtOH (fruits only)
Extracts from leaves and stems appear similarly efficient at inhibiting metmyoglobin-initiated lipid oxidation in both BSA- and PL-stabilized emulsions at pH 5 (49-73%). Leaves containing 75%
(w/w) in chlorogenic acids proved to be the best antioxidant extract in the BSA model.
Extracts from fruit were added at twice the level compared to stem and leaf.
Extract with 55% aq. EtOH has a higher content in phenolic compounds and is also more efficient than the aqueous fruit extract.
Leaf and stem extracts have no ability to inhibit lipid oxidation at pH 3 in PL model (data not shown)
NB: standards were used at 100 μM levels.
Extracts of bilberry stems, leaves and fruits:
Can they protect dietary lipids from oxidation during digestion in in vitro conditions?
2. Dried Extracts (DE)
0 20 40 60 80 100 120
Leaves Stems Fruit/water Fruit/EtOH55% Chlorogenic acid (–)-Epicatechin Procyanidin A2 Cyanidin-3-gal.
% Inhibition over 4 h
BSA model PL model